Vaporizer for oil engines



sept; 25, 1934.v

. F. PoRscHE vAPoRIzER FOR OILENGINES Filed Oct. 22. 1928 liti Patented Sept. 25, 1934 1,974,785 vnronlznal Fon on. ENGINES Ferdinand Porsche,

Germany, assgnor 13 Claims.

lllhis invention relates to internal combustion engines and has for its object to provide a special form of vaporizer and atomizer which is inserted as a liner into the opening between the ignition chamber and the compression space in the cylinder of ignition chamber engines.

In most of the arrangements of this kind at `present in use the communication is established through a set of fine openings. The fuel is thus injected in a number of very line jets into the compression space and along the path of each separate jet of fuel amixing of air and fuel takes place, while the bulk of theair between'the separate jets remains unmixed. With a single central opening in a normal vaporizer a suliicient mixing of the air with the fuel can by no-means be ensured.

According to the invention a very complete mixing of the air with the fuel in the' compression space of the cylinder is produced by the fuel being sprayed in 'the form of a flat, conical shell, so that it permeates every layer in the compression space.

This is eifected by the peculiar form of the vaporizer in conjunction with the vaporizer insertion introduced into its lower part. lThe said insertion consists of a fixing plate and a cylindrical member which extends into the lower part of the vaporizer and having its lower end terminating in a ilat conical point. The bottom of the vaporizer is a flat hollow cone of similar shape so that between the two parts a conical annular gap is formed.

In the ignition chamber the following takes place:

The fuel is injected by the atomizing nozzle in a conical shell into the ignition chamber, Where it is torn apart by the air flowing through the vaporizer out of the compression space of the cylinder and is thoroughly mixed with the air in the combustion chamber.

A portion of the fuel is thereupon ignited and by the highly compressed combustion gases thus developed the remainder of the fuel is conveyed to the vaporizer. In the latter it is gathered together in the narrow vaporizer passages into a closed hollow cylindrical jet and is thereupon sprayed through the conical annular gap in the form of a thin shell into the compression space. In this way all parts of the compression space are supplied uniformly with fuel. This results in a rapid and complete combustion, the fuel being thus very completely utilized.

In the accompanying drawing a constructional example of the arrangement is shown,

' this costly material to a minimum, it will be found Stuttgart Unterturkheim, to Daimler-Benz, Aktiengesellschaft, Stuttgartheim, Germany, a German company Application October 22, 1928, Serial lin Germany January 8, 1926 (Berlin) Unterturk- Fig. l being a longitudinal section through the centre line of the spraying nozzle, the ignition chamber and the vaporizer and Fig. 2 a cross-section through the ignition chamber, with the vaporizer in plan View.

In the head a of the cylinder a fuel nozzle is provided, which is closed by the fuel needle c.

The latter may be controlled in a known manner by the fuel which is introduced under pressure.

In the communicating passage between the ignition chamber f and the compression space of the cylinder the vaporizer and atomizer h is inserted in the form of 'a sleeve. The passages which give the fuel jet its form and direction when being sprayed in are formed by the insertion z', g. This insertion consists of an upper disc i containing passages between which are the narrow bridging pieces m for supporting the inser tion, and the lower cylindrical part g. Between the part g and the wall of the Vaporizer h there is a narrow passage lc in the form of a cylindrical ring. rIhe lower end of the cylindrical part g terminates in a flat conical part which together with the hollow conical bottom of the vaporizer forms the conical annular gap required for giving the .desired shape to the sprayed in jet of fuel. A hole in the middle of the bottom of the vaporizer establishes communication with the compression space of the cylinder.

Owing to the high temperatures prevailing at this point and the very small amount of conveyance away of heat through the' thin arms m the insertion i, g must be made of special refractory material. In order to reduce the amount of of advantage for the cylindrical part y which is more particularly exposed to excessive wear to be inserted in the disc i in the form of a removable pin. It is then only necessary to make this pin g' of the costly refractory material, which may be replaced in a simple and convenient manner.

This invention is adapted for use with Diesel engines of the type in which the liquid fuel is injected without the aid of compressed air.

With reference to the part g, i, m Fig. 3 shows a further constructional example according to which is provided a series of circular apertures n opening into the annular passage 1c. The vertical distance of said apertures n from the .exitl channel communicating with the working cylinder may be larger or smaller than is represented in Fig. 1.

What I claim is:

1-. In an injection internal combustion engine with a combustion chamber and an ignition chamber, a nozzle opening into the ignition chamber, through which fuel is injected into the ignition chamber, a substantially plane atomizing plate arranged in the ignition chamber at right angles to the direction of the jet .of fuel leaving the nozzle, this atomizing plate being formed with holes arranged substantially circularly round the axis of the jet of fuel, a core piece located beyond the atomizing plate in the direction of the jet, this core piece having an apex directed towards the combustion chamber, and being spaced away from the surrounding wall of the ignition chamber, the holes in the atomizing plate opening into the space between the core piece and the said wall, an inwardly directed annular projection in this wall, surrounding the apex of the core piece, shaped to correspond substantially to the said apex, and leaving free round the apex a short wide aperture leading into the combustion chamber.

2. In an internal combustion engine with a combustion chamber and an ignition chamber, a nozzle through which the fuel required for each working stroke is injected into the ignition chamber, Where it is partially ignited by the heat of compression, the ignition chamber consisting of two parts differing from one another in crosssectional area, so arranged that the fuel nozzle sprays the fuel through the part of greater crosssectional area into the part of smaller cross-sectional area, a perforated atomizing plate in the part of smaller cross-sectional area, facing the fuel nozzle and arranged perpendicularly to the fuel nozzle, an annular passage beyond the atomizing plate, the perforations in the atomizing plate opening into the said passage, a core piece having its end tapered towards the combustion chamber, said core piece being surrounded by a passage, and an inwardly directed annular flange partly screening the core piece from the combustion chamber and shaped to correspond substantially with the form of the core piece whereby to form a passage substantially in the form of the surface of a cone opening at its apex into the combustion chamber.

3. In an internal combustion engine with a combustion chamber and an ignition chamber, a nozzle opening into the ignition chamber, through which fuel is injected into the ignition chamber and partially ignited, a vaporizing and atomizing sleeve lining a portion of the wall of the ignition chamber and receiving the jet of fuel discharged from the nozzle, a core piece coaxially arranged within the sleeve and having its end tapered towards the combustion chamber, bridging arms connecting the core piece with the sleeve, and an inwardly directed annular flange at the end of the sleeve shaped to correspond substantially to the form of the core piece, in such a way as to form a passage substantially in the form of the surface of a cone opening at its apex into the main combustion chamber.

4. In an internal combustion engine with a combustion chamber and an ignition chamber, a nozzle arranged at the side of the ignition chamber remote from the combustion chamber in the axial direction of the ignition chamber, through which nozzle fuel is injected into the ignition chamber, and there partially atomized, the ignition chamber consisting of two parts differing from one another in cross-sectional area, so arranged that the fuel nozzle sprays the fuel through the part of greater cross-sectional area into the part of smaller cross-sectional area,A a sleeve which substantially completely surrounds the said part of smaller cross-sectional area, an atomizing plate connected with the sleeve and arranged perpendicularly to the jet of fuel, formed with apertures arranged substantially in a circle, a core piece connected with the atomizing plate. surrounded Yby the sleeve and tapered at the end towards the combustion chamber, and an annular projection on the sleeve, directed inwards and partly screening the core piece from the combustion chamber and shaped substantially to correspond to the form of the end of the core piece, in such a way that the substantially annular passage between the core piece and the sleeve opens into the combustion chamber at the apex of the core piece.

5. In an injection internal combustion engine with a combustion chamber, an ignition chamber and a nozzle through which the fuel is injected into the ignition chamber without air, a sleeve of substantially hollow cylindrical form in the ignition chamber, a core piece located in the sleeve, bridging arms connecting the core piece with the sleeve, a further sleeve, which is mechanically connected with the rst sleeve and forms a prolongation thereof, and projections on this second sleeve, which partly screen the core piece from the combustion chamber.

6. In an internal combustion engine with fuel injection and provided with 'a main combustion chamber, an ignition chamber and a nozzle, 105 through which the fuel is injected into the ignition chamber, said ignition chamber and said combustion chamber being in constant communication by means of a central opening, a core piece which with respect to the direction of flow of the fuel from the nozzle to the main combustion chamber is situated in advance of said opening, in such a way that between the end of the core piece adjacent the opening and the walls surrounding said core piece a passage is left open which leads to said opening.

'7. In an internal combustion engine with fuel injection and provided with a main combustion chamber, an ignition chamber and a nozzle, through which the fuel is injected into the ignition chamber, the ignition chamber and the main combustion chamber being in communication through an opening, a core piece, arranged in advance of said opening with respect to the direction of the fuel jet issuing from the injection nozzle and against which the jet is directed, said core piece being constituted by a cylindrical body merging into a cone in the direction of the said opening, in such a way that between said core piece and the walls of the ignition chamber, surrounding it, a passage to said opening is obtained, which has a substantially circular cross section and which is shaped like the surface of a cone.

8. In an internal combustion engine with fuel injection and provided with a main combustion chamber, an ignition chamber and a nozzle, through which the fuel is injected into the combustion chamber, the ignition chamber and thc main combustion chamber being in constant communication through an opening, a core piece 140 which, with respect to the direction of the fuel jet issuing from the nozzle is arranged in advance of said opening, in such a way that an uninterrupted passage of the fuel jet through said opening is prevented, arms connecting the core piece with 145 the surrounding walls of the ignition chamber in such a way, that a passage is obtained leading to said opening between the core piece and the outer walls, said passage being partly interrupted by the arms.v

9. In an internal combustion engine with fuel injection and provided with a main combustion chamber, an ignition chamber and a nozzle, through which the fuel is injected into the ignition chamber, said ignition chamber and said combustion chamber being in constant communication by means of an opening, a core piece which With respect to the direction of flow of the fuel from the nozzle to the main combustion chamber is situated in advance of said opening and is shaped like a cone at one end with the apex situated in the direction of the main combustion chamber, an inwardly projecting ange on the wall surrounding the core piece, said flange having a corresponding cone like shape, in such a Way that the passage obtained between said core piece and said flange is shaped like the mantle surface of a cone, the apex of which is situated essentially at the point where the above mentioned admission opening, through which said passage and the main combustion chamber communicate, opens into said main combustion chamber.

10. In an internal combustion engine with fuel injection and provided with a main cornbustion chamber, an ignition chamber and a nozzle through which the fuel is injected into the ignition chamber, said ignition chamber and said main combustion chamber being in constant communication by an opening, a core piece in said ignition chamber arranged before the admission opening leading from said ignition chamber to said main combustion chamber, said core-piece being shaped like a cone at the end nearest to the main combustion chamber, and said opening decreasing in diameter in the direction of taper of the conical end of the core piece and forming a passage in the form of the mantle surface of a cone, the apex of said passage forming the admission opening into the main combustion chamber, the nozzle being arranged to direct the fuel jet issuing therefrom against said core piece, and spaced arms connecting the core piece with the wall of said opening, the fuel jet from said nozzle passing between said arms into said passage. l

1l. In an internal combustion engine with fuel injection and provided with a main combustion chamber, an ignition chamber and a nozzle through which the fuel is injected into the ignition chamber, said ignition chamber and said main combustion chamber being in constant communication by means of an opening, a core piece in said ignition chamber arranged before the admission opening leading from said ignition chamber to said main combustion chamber, said core-piece being shaped like a cone at the end nearest to the main combustion chamber, and said opening decreasing in diameter in the direction of taper of the conical end of the core piece and forming a passage in the form of the mantle surface of a cone, the apex of said passage formn ing the admission opening into the main combustion chamber, the nozzle being arranged to direct the fuel jet issuing therefrom against said core piece, and arms connecting the core piece with the surrounding Wall of the ignition chamber and forming passages therebetween for the fuel jet from said nozzle, the last mentioned passages being disposed in substantial parallel ikgelation to the central axis of the ignition chamwith a combustion chamber and an ignition chamber, a nozzle through which the fuel re quired for each working stroke is injected into the ignition chamber, where it is partly ignited by the heat of compression, a bale plate arranged in the ignition chamber in the path of the fuel, and a core piece arranged in the ignition chamber behind the bale plate, With respect to the direction of now of fuel, and having its outer end in the form of a cone the apex of Which is directed towards the combustion chamber, a passage being v provided between the core ypiece and the surrounding wall which is in the shape of a hollow cone, the apex of which is directed towards the combustion chamber and merges directly into it. 13. In an internal combustion engine with fuel injection and provided with a main combustion chamber, an ignition chamber and a nozzle, through which the fuel is injected into the ignition chamber, the ignition chamber and the main combustion chamber being in communication through a throttling connection, a core piece which, with respect to the direction of the flow of the fuel from the nozzle to the main combustion chamber is arranged in advance of said throttling connection, arms connecting the core piece with the surrounding walls of the ignition chamber, in such a way that a passage is obtained leading to said throttling connection between the core piece and the outer walls, said passage being partly interrupted by the connecting arms. 

